HVEM and nectin-1 are the major mediators of herpes simplex virus 1 (HSV-1) entry into human conjunctival epithelium. Invest Ophthalmol Vis Sci 2008 Sep;49(9):4026-35
Date
05/27/2008Pubmed ID
18502984Pubmed Central ID
PMC2569872DOI
10.1167/iovs.08-1807Scopus ID
2-s2.0-53149088561 (requires institutional sign-in at Scopus site) 61 CitationsAbstract
PURPOSE: The human conjunctiva is a natural target for herpes simplex virus (HSV)-1 infection. The goals of this study were to investigate the cellular and molecular mechanisms of HSV-1 entry into human conjunctival epithelial (HCjE) cells. Specific features of entry studied included the method of initial viral binding to cells, pH dependency, and expression and usage of specific HSV-1 entry receptors.
METHODS: To observe HSV-1 initial binding, live cell imaging was performed on HSV-1-infected HCjE cells. Reporter HSV-1 virions expressing beta-galactosidase were used to determine entry of wild-type HSV-1(KOS) and a mutant, HSV-1(KOS)Rid1, into HCjE cells. HSV-1 replication in HCjE cells was determined by plaque assays. Lysosomotropic agents were used to determine whether viral entry was pH dependent. Reverse transcription (RT)-PCR, flow cytometry, and immunohistochemistry were used to determine the expression of receptors. Receptor-specific siRNAs were used to define the role of individual entry receptors.
RESULTS: HSV-1 virions attach to filopodia present on HCjE cells and use them to reach the cell body for entry. Cultured HCjE cells demonstrate susceptibility to HSV-1 entry and form plaques confirming viral replication. Blocking vesicular acidification significantly reduces entry, implicating a pH-dependent mode of entry. Multiple assays confirm the expression of entry receptors nectin-1, HVEM, and 3-O-sulfated heparan sulfate (3-OS HS) on the HCjE cell membrane. Knocking down of gD receptors by siRNAs interference implicates nectin-1 and HVEM as the major mediators of entry.
CONCLUSIONS: HSV-1 entry into HCjE cells is a pH-dependent process that is aided by targeted virus travel on filopodia. HCjE cells express all three major entry receptors, with nectin-1 and HVEM playing the predominant role in mediating entry.
Author List
Akhtar J, Tiwari V, Oh MJ, Kovacs M, Jani A, Kovacs SK, Valyi-Nagy T, Shukla DAuthor
Sandor K. Kovacs MD Assistant Professor in the Pathology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsCHO Cells
Conjunctiva
Cricetinae
Cricetulus
Epithelial Cells
Herpes Simplex
Herpesvirus 1, Human
Humans
Intermediate Filament Proteins
Nerve Tissue Proteins
Nestin
Pseudopodia
Receptors, Tumor Necrosis Factor, Member 14
Viral Plaque Assay
Virus Internalization
